Nickel Sulphate Nickel Sulphateis an Inorganic compound with the formula NiSO4(H2O)6. This highly soluble blue-coloured salt is a common source of the Ni2+ ion for electroplating. Anhydrous Nickel sulfate is a yellow-green crystalline solid. The compound can contain variable quantities of water, depending on their previous exposure to moisture or conditions. Nickel Sulphate is mildly toxic and carcinogenic. The chemical compound is denser than water. It is highly dangerous for the environment. The chemical is used to make other nickel compounds for printing and textile industries.